CDC works very closely with state and local officials in areas where human cases of new H1N1 flu infections have been identified. CDC has deployed staff to several states to assist with the investigation of the impact of the novel H1N1 influenza, including the assessment of the severity of illness, how easily the virus spreads, and the amount of time people may be infectious. In states where EpiAid teams have been deployed, many epidemiological activities are taking place or planned including:

  • Active surveillance in the counties where infections in humans have been identified;
  • Studies of health care workers who were exposed to patients infected with the virus to see if they became infected;
  • Studies of households and other contacts of people who were confirmed to have been infected to see if they became infected; and
  • Study to see how long a person with the virus infection sheds the virus.

This virus was originally referred to as “swine flu” because laboratory testing showed that many of the genes in this new virus were very similar to influenza viruses that normally occur in pigs in North America. But further study has shown that this new virus is very different from what normally circulates in North American pigs. It has two genes from flu viruses that normally circulate in pigs in Europe and Asia and avian genes and human genes. Scientists call this a “quadruple reassortant” virus.

Spread of H1N1 (swine) flu can occur in two ways:

  • Through contact with infected pigs or environments contaminated with swine flu viruses.
  • Through contact with a person with H1N1 (swine) flu. Human-to-human spread of H1N1 (swine) flu has been documented also and is thought to occur in the same way as seasonal flu. Influenza is thought to spread mainly person-to-person through coughing or sneezing of infected people.

 

If you live in areas where people have been identified with new H1N1 flu and become ill with influenza-like symptoms, including fever, body aches, runny or stuffy nose, sore throat, nausea, or vomiting or diarrhea, you should stay home and avoid contact with other people, except to seek medical care. If you have severe illness or you are at high risk for flu complications, contact your health care provider or seek medical care. Your health care provider will determine whether flu testing or treatment is needed.